The Mutual Assurance Society v. Watts' Executor was a case heard by the United States Supreme Court in 1816. The court considered whether an insurance company could be held liable for damages caused by fire when it had not been notified of the risk prior to the incident occurring. The plaintiff, Watts' Executor, argued that they were entitled to compensation from the defendant, Mutual Assurance Society (MAS), as MAS had issued a policy on their property and should have known about any risks associated with it. On appeal, however, MAS argued that since they had not been informed of any potential hazards before issuing their policy or at any time thereafter until after the fire occurred, they should not be held responsible for compensating Watts’ Executor for losses suffered due to said fire. In its ruling on this matter, the Supreme Court found in favor of MAS and ruled that since no notice was given prior to issuance of coverage or during its term regarding potential risks associated with insured property; therefore there can be no liability imposed upon them under these circumstances.

In The Mutual Assurance Society v. Watts' Executor, the Supreme Court was asked to decide whether a policy of insurance issued by an English company could be enforced in Virginia. The majority opinion held that the policy was not enforceable because it had been made under foreign law and did not conform to Virginia's laws regarding contracts. However, Justice Story dissented from this decision on the grounds that there were no applicable state laws which would have prevented enforcement of the contract in question. He argued that since both parties had agreed to abide by English law when entering into their agreement, they should be bound by its terms regardless of any conflicting state statutes or regulations. Furthermore, he noted that allowing such contracts to stand would promote international commerce and foster good relations between nations as well as encourage citizens from different countries who wished to do business together without fear of being denied justice due to differences in local laws or customs.